Rule of thumb 1 tbs of extract per gallon. I use Splenda about 1.5 cups per gallon. Basically make it taste a little too sweet, just a bit, chill & force carb. I often add a bit of vanilla, I'd also use the white sugar, it's all preference.
My blog site will contains adventures from time to time, Blog
Here is my twitter feed as well. Twitter
This is an adventure.